# perl > The Perl 5 language interpreter. > More information: . - Parse and execute a Perl script: `perl {{script.pl}}` - Check syntax errors on a Perl script: `perl -c {{script.pl}}` - Parse and execute a Perl statement: `perl -e {{perl_statement}}` - Run a Perl script in debug mode, using `perldebug`: `perl -d {{script.pl}}` - Loo[p] over all lines of a file, editing them [i]n-place using a find/replace [e]xpression: `perl -p -i -e 's/{{find}}/{{replace}}/g' {{filename}}` - Run a find/replace expression on a file, saving the original file with a given extension: `perl -p -i'.old' -e 's/{{find}}/{{replace}}/g' {{filename}}` - Run a multiline find/replace expression on a file, and save the result in another file: `perl -p0e 's/{{foo\nbar}}/{{foobar}}/g' {{input_file}} > {{output_file}}` - Run a regular expression on stdin, printing out the first capture group for each line: `cat {{path/to/input_file}} | perl -nle 'if (/.*({{foo}}).*/) {print "$1"; last;}'`